Dry cell



Oct.'` 12 1926.

. G'. M. LITTLE ET AL DRY CELL yFiled slept. 27; 1922 INVENTORS GeorgeVhbittka and James G Ford BY v ATTORNEY WITN ESSES:

remuaoa. 12, 192s. 1,602,915

1 UNITED STATES PATENTol-Flca asoma n. 1.1mm, or rrrrsnnnen, Am :Anas e.ronn, or wmxmsnuas, PENN- snvANIA, Asszenons 'ro wnsrmenousn nLncrnIo eMANUFACTURING con-` rANY, A conroaArxoN or rmsnvAmA.

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Application med September 27, 1922. Serial No. 590,781.

This invention relates to dry cells, more to considered essentialincells of this kind:` particularly'to that type of dry cell which Inpractising our invention, we provide 55 1s used in radio apparatus andis known as a glass container, generally about two the B battery. incheshi h and 1% inch in dia-meter in the e In batteries of this typepreviously used, bottom o which is placed a heavily amalthe cellconsistedof a zinc cup lined with gamated lzinc plate to which a leadwire athin layer oi" a starch-paste mixture conis secured by anysuitable means. .A starch @il taining ammonium chloride and zincchlopaste containing the electrol te is placed ride. Within thecontainer was placed a on the zinc plate and a depo arizing paste porouscup of paper which was filled with a is placed thereupon. A carbon-rodanode depolarizer, generally consisting of a. mixprojects into thedepolarizer, and the cell ture or" manganese dioxide and carbon. In 1ssealed with suitable wax. ce some cases, the paper was dispensed with Inthe accompanying drawing constitutand a cloth bag filled with adepolarizer ing a part hereof and in which like. referwas placed withinthe container. The cell ence characters indicate like parts,

was tightly sealed with ordinary sealing The single ligure is a verticalcross-sec- Wsq, tional view of a cell made in accordance Cells vmade inthis manner were capable with our invention.

of giving good service in radio apparatus We provide a container 1 etinsulating but the quality o'such cells was uncertain material,generally 'consisting of glass and owing to, in a large measure, therapid being cylindrical 1n shape, For a B loatdeterioration thereof onstanding. The `tery, We generally utilize those glass conlarge area ofcontact between the zinc and tainers which are known as specimen thestarch paste and depolarizer and the tubes. In the bottom of thecontainer relative thinness of the starch paste allowed -1 lis placed ametal plate 2 consisting of a chemical action to proceed withcomparaheav1ly amalgamated sheet of zinc having a tively great rapidity,thereby deteriorating plurality yof openings 3 therein. A copper 8 thecell whether or not it was used. The lead wire 4, the lower end et whichis amalcell was also expensive to make and only amated, is inserted insaid openings and 3o' a small part of the zinc therein was used ent toanchor the same to the plate. W e in generating a useful electriccurrent. may provide a layer or coating 5 ot copper Most of the zinc wasrendered useless for on the lower side of the plate 2 before amal- 85current-producing urposes when the elecgamating in order to malte morecertain trolytic action in t e cell formed. holes in contact bet-Weenthe plate and the lead wire.

35 a few places in the zinc cup. A glass tube Gsurrounds the lead wiret,

Such cells are generally assembled in. the lower end 7 thereof beingsealed with units-ot about l5 to provide the necessary starch aste. Theelectrolyte 8 consists oi so voltage for-a B battery. Because of the astare -paste mixture containing' about 40 necessity for a compact cellunit, each of parts starch, 30 parts ammonium chloride, such cellspreviously used had tobe insulated 2O parts zinc chloride and 26 partswater. from each other after assembling in order` The mixture is pouredinto the container to prevent the accidental short-circuitinguntilasuiiicient thickness of layer has been thereof. This addedinsulatin further in formed to setand become semi-solid.

creased the cost of making such cells. The -depolarizing mixture 9consists of 45 The present invention 1s designed to ob about 40partsmanganese dioxide, 16 parts viate the disadvantages of cells previouslygraphite, 3 parts ammonium chloride, 1.2

made, it bein amon the objects thereof to parts zinc chloride andsuiicient water to provide a cel of tie type. hitherto used make astili' paste. The depolarizer is which shall be relatively simple inconstrue placed upon the electrolyte 8 in direct contion, which may bereadily assembled at a tact therewith. A carbon rodlO, which has smallcost, which shall have a relatively been impre ated with parallin,projects inlong life, both when in use and when idle, to the depo arizer9 and has a metal cap 11 10 nd'which shall dispense with parts hitheronthe upper end thereof, The cap 11 may A layer 18 of separatin material,such as aper, is placed on the epolarizer 9 and a t 1in layer ofadhesive wax 14 spread on the walls of container 1 above the paper layer13. Ordinary sealing wax 15 is tpoured into the top of the container toll the same and seal the cell from the atmos here. The top 16 of tube 6is sealed with ad esive wax similar to wax 14.

A cell constructed in accordance with our invention has a number ofadvantages over the cell previously used. The glass container obviatesthe necessity for insulation, such as Wax paper, between adjacent cells.It also makes feasible the use of amalgamated zinc in the cell, therebypreventing local action and the generation of gases because ofimpurities in the zinc. A cheap grade of zinc may be utilized and a muchless quantty thereof is necessary in a cell having the same ampere hourcapacity as prior cells. It allows the ready inspection of a completedcell.

The small area of zinc exp .ised to chemical action, the relativelysmall cross-section of the starch layer in contact with they depolarizerand the comparatively great thickness of the starch layer limit thediffusion in the cell and contribute to greatly limit the short-circuitoutput of the cell, rendering it capable of withstanding considerableabuse, such as a short circuit for an hour, with but very littlepermanent damage. Such a cell will recuperate in a day to near y itsfull value.

This has the further desirable result that the cell, if accidentallyshort-circuited, will not rise in temperature as much as the zinccupcell of the old type, thereby further lessening chemical action and theconsumption of the active ingredients of the cell, at the same timelessening the danger of softening of the wax seal. This feature makesthe cell of `no use .where heavy work is demanded. but it makes it aln 1ost fool-proof as a B battery where only .003 ampere is required.

Placing the zinc fiat in the bottom of the cell lessens that localaction which is, in the zinc-cup cell, caused by the zinc being exposed.in its different parts, to electrolytes of different strengths, theso-called concentration cell eifect, which is caused by the lower layersof electrolyte being of reater concentration than the upper layers. tprevents the zinc .from being consumed in service more rapidly in onepart than another and it makes possible the useful consum tion of nearlall the zinc.

T e omission o the cloth or paper separator and the replacement thereoby a thlck layer of starch electrolyte set in place by heat does awaywith the danger of particles of depolarizer mixture Working their waythrough the pores of the cloth or paper and making contact with thezinc, causing an internal short circuit. It* greatly lessens laborandexpense of assembly of the cell.

We claim as our inventiomy 1. A cell comprising a container ofnonconductinfr material, a metal plate yin the bottom tiereof, aterminal wire secured thereto, a tube of non-'conducting materialsurrounding said terminal wire, the u per end of said tube bein sealedby wax an the lower end by a stare paste, an electrolyte on said plate,a depolarizer on said electrolyte, and an electrode in saidydepolarizer.

2. A cell comprising a container of nonconducting material, a metalbottom thereof, a vterminal wire threaded and secured to said plate, alayer of semisolid material containing electrolyte superimposed on saidplate and in contact onl with said plate e ectrode, a layer of semlsolidmaterial containing a depolarizer superim osed on said electrolyte, anelectrode embe ded in said de olarizer and in contact only therewith anmeans for insulating sai terminal wire from said depolarizer.

3. A cell comprising a container of nonconducti-ng material, a metalplate in the bottom thereof, a terminal wire secured thereto, a layer ofsemisolid material containing electrol te over said plate and in contactonly witli said plate, a la er of semisolid material containing a depoarizer over said electrolyte, an electrode embedded in said depolarizerand a sealed tube of insulating material extending through said layer ofdepolarizer into said layer of electrolyte.

4. A cell comprising a container of nonconducting material, a layer ofsemisolid material containing a depolarizer superimposed on a layer ofsemisolid material containin an electrolyte, a metal late embedde insaid electrolyte, an insulating tube extending through said layer ofdepolarizer intio said layer of electrolyte, a terminal adapted to makecontact with said plate sealed in and extending through said tube, and acarbon rod provided with another terminal embedded in said layer ofdepolarizer material.

In testimonyl whereof, we have hereunto subscribed our names this 21stday of September, 1922.

GEORGE M. LITTLE. JAMES e. reen,

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